New NASA images show possible microbial life on Mars

A scientific study of a set of images taken from orbit by NASA's Mars Global Surveyor has found evidence of recent water flow on the surface of the Red Planet, raising the possibilities of existence of microbial life on Mars.

The new satellite images of craters on Mars, taken in 2004 and 2005, when compared to those taken five years ago, depicted bright new deposits in two gullies on Mars, clearly defining that water carried sediment through them sometime during the past seven years.

"These observations give the strongest evidence to date that water still flows occasionally on the surface of Mars," Michael Meyer, lead scientist for NASA's Mars Exploration Program, Washington, said in a press conference yesterday.

"The Mars orbiter camera has seen changes in the surface of the planet within the last seven years, highlighting critical processes that have altered that surface," Meyer said.

In the images, the shape of the deposits is seen as the flowing water gives to the debris it carries along. According to the scientists, the deposits have finger-like branches at the end of the slope and are easily diverted around small impediments.

Also, an emergence of a lightly-shaded patch in two images of the same crater, taken in August 1999 and September 2005, respectively, gives the clear -cut signs of presence of water that is moving upwards in bubbles from under the Martian surface and flowing down the 30 degree slope.

"These fresh deposits suggest that at some places and times on present-day Mars, liquid water is emerging from beneath the ground and briefly flowing down the slopes. This possibility raises questions about how the water would stay melted below ground, how widespread it might be, and whether there's a below-ground wet habitat conducive to life. Future missions may provide the answers," said Michael Malin of Malin Space Science Systems, San Diego.

Malin is the principal investigator for the Mars Orbiter Camera on NASA's Mars Global Surveyor and lead author of a report about the findings published Wednesday in the journal Science.

Liquid water, as opposed to the water ice and water vapour known to exist at Mars, and a permanent heat source are considered necessary for life. Scientists have long been trying to prove the age-long existence of liquid water flowing on the surface of the Red Planet.

The new findings, which came after examining nearly 240,000 images from Surveyor, are a major step forward for NASA in its hunt to reveal the Mars secrets and determining the age of features on the surface of Mars.

Mars Global Surveyor began orbiting Mars in 1997 and its camera photographed approximately 98 percent of Mars in 1999 and nearly 30 percent in 2006.

NASA has not heard from the spacecraft since early November. The space agency is trying to locate the spacecraft, which is responsible for many significant discoveries and was last heard from on Nov. 5.